White ink, ink set, recording method, ink container, and inkjet recording device

Abstract

A white ink containing one or more organic solvents including 40 percent by mass or more of an amide compound of formula 1 is provided: wherein, R 1 represents a straight-chained or branch-chained alkyl group having one to six carbon atoms, R 2 and R 3 each, independently represent hydrogen atoms or straight-chained or branch-chained alkyl groups having 1 to 4 carbon atoms.

What is claimed is: 
     
       1. A white ink comprising:
 a metal oxide; 
 polyurethane resin particles having a glass transition temperature of 0 degrees C. or lower; and 
 an organic solvent comprising an amide compound of formula (1), 
 wherein an amount of the amide compound of formula 1 is 40 percent by mass or more of the organic solvent, 
 
       
         
           
           
               
               
           
         
         wherein R 1  represents a straight-chained or branch-chained alkyl group having one to six carbon atoms, and R 2  and R 3  each, independently represent hydrogen atoms or straight-chained or branch-chained alkyl groups having 1 to 4 carbon atoms. 
       
     
     
       2. The white ink according to  claim 1 , wherein the amount of the amide compound of formula 1 is from 60 percent to 80 percent by mass of the organic solvent. 
     
     
       3. The white ink according to  claim 1 , further comprising a polysiloxane-based surfactant. 
     
     
       4. The white ink according to  claim 1 , wherein a content of the polyurethane resin particles is from 1 to 15% by mass of the white ink. 
     
     
       5. The white ink according to  claim 4 , wherein the polyurethane resin particle is selected from the group consisting of polyether-based polyurethane resin particles, polycarbonate-based polyurethane resin particles, polyester-based polyurethane resin particles mixtures thereof. 
     
     
       6. An ink set comprising:
 the white ink according to  claim 1 ; and 
 a non-white ink. 
 
     
     
       7. The ink set according to  claim 6 , wherein the non-white ink comprises an organic solvent comprising an amide compound of formula (1): 
       
         
           
           
               
               
           
         
         wherein R 1  represents a straight-chained or branch-chained alkyl group having one to six carbon atoms, and R 2  and R 3  each, independently represent hydrogen acorns or straight-chained or branch-chained alkyl group having 1 to 4 carbon atoms. 
       
     
     
       8. The ink set according to  claim 7 , wherein an amount of the amide compound of formula 1 is 40 percent by mass or greater of the organic solvent of the non-white ink. 
     
     
       9. The ink set according to  claim 8 , wherein the amount of the amide compound of formula 1 is from 60 percent to 80 percent by mass of the organic solvent in the non-white ink. 
     
     
       10. The ink set according to  claim 6 , wherein the non-white ink further comprises a polysiloxane-based surfactant. 
     
     
       11. The ink set according to  claim 6 , wherein the non-white ink further comprises polyurethane resin particles. 
     
     
       12. The ink set according to  claim 11 , wherein a glass transition temperature of the polyurethane resin particle is 0 degrees C. or lower. 
     
     
       13. A recording method comprising:
 discharging the white ink according to  claim 1  and optionally, a non-white ink on a substrate to form an image thereon; and 
 drying the image. 
 
     
     
       14. An ink container comprising:
 the white ink according to  claim 1  and optionally, a non-white ink; and 
 one or more ink accommodating units configured to include the white ink and optionally, the non-white ink. 
 
     
     
       15. An inkjet recording device comprising:
 the ink container according to  claim 14 ; and 
 an ink discharging device configured to discharge the white ink and optionally, the non-white ink accommodated in the ink container. 
 
     
     
       16. The white ink according to  claim 1 , further comprising a white pigment. 
     
     
       17. The white ink according to  claim 16 , wherein the white pigment is a metal oxide selected from the group consisting of titanium oxide, iron oxide, tin oxide, zirconium oxide, and iron titanate. 
     
     
       18. The white ink according to  claim 16 , wherein a whiteness value of the white ink according to ISO-2469 (JIS-8148 format) is 70 or greater.